The influence of the high-risk care environment on the practice of low-risk obstetrics.

This retrospective chart review compared the intervention rates in 2,365 low-risk obstetric patients at three urban teaching hospitals, two of which were high-risk, perinatal referral centers. The third cared for mostly low-risk patients. The hypothesis was that rates of intervention in low-risk pregnancies would be higher in the high-risk care environment. Family physicians at the perinatal referral centers performed significantly more artificial rupture of membranes, epidural blocks, augmentations of labor, and episiotomies on their low-risk patients than did those at the low-risk hospital. This trend was also found for obstetricians but did not reach statistical significance. Thus, the conclusion was drawn that caring for low-risk patients in a high-risk care environment is associated with a higher intervention rate by family physicians. Factors that may contribute to this finding are discussed.